3D technology is getting more advanced, but many systems force the viewer into a single perspective quite unlike the way we view actual 3D images. MIT Media Lab is trying to develop a glasses-free screen called a Tensor Display that uses multiple layered LCDs to create an illusion that can be viewed from multiple perspectives. First announced for SIGGRAPH's Emerging Technologies showcase, the technology has now been explained in much more detail at the MIT news office. Basically, a different portion of each video frame is displayed on one of the three LCDs, and pattern-calculating algorithms cause the screen to flicker as it displays multiple images that appear to change the picture based on perspective.
The requires a refresh rate of 360 Hz, something that's currently seen mostly in high-end HDTVs, but it doesn't require the massive investment of something like a full hologram. Layered screens are already used in other products, like the Nintendo 3DS, and this project could advance the effects well beyond what we see today.
Update: The explanation was at the MIT News Office, not MIT's Technology Review